The incident comes just weeks after the company had marked national mine safety week.
The company in a statement released yesterday, said the incident had occurred at about 7.50am on Monday.
The management said the cause of the accident is yet to be established.
It confirmed that the deceased employee was an expatriate from China.
The company said every effort had been made by its emergency response team which included medical officers to resuscitate the worker but without success.
The management said the two national staff who sustained injuries were airlifted from Basamuk, Raicoast District to Madang and are now recovering at the Modilon General Hospital.
"The incident was unfortunate and we are so sad that we have lost one of our employees.
"We are in the process of informing his family members," the management said.
The incident has been reported to Mineral Resources Authority and the incident scene has been barricaded for further investigation.
"We have secured the area and ensured no further injury to our employees. We also advise family members and relatives that all employees are all safe," Ramu NiCo management said. Post Courier